In some of today's automotive applications, higher flow rate fuel pumps are necessary to keep up with increased engine demand at wide open throttle. A typical mechanically regulated system uses a fuel regulator to deliver the exact amount of fuel necessary to the engine, and returns the unused fuel back to the fuel module. When that same vehicle is running at idle, nearly all of the fuel output from the fuel pump is directed through the pressure regulator. Due to the design of the regulator, the fuel is sheared as it passes through the regulator, vaporizing the fuel and creating small bubbles. This shearing of the fuel and generation of bubbles in turn causes an audible noise to be generated from the pressure regulator. This noise is often audible inside the passenger compartment and is undesirable to the customer.
Thus, there is a need to prevent the bubbles from forming and creating noise at the outlet of a fuel regulator.